When creating a mask pattern used for double patterning such as LELE (Litho-Etch-Litho-Etch), and the like, a design layout completed with DRC (Design Rule Check) is divided for double patterning. Two mask patterns are generated as a result of such division. An LCC (Lithography Compliance Check) is executed on the mask patterns used for the double patterning, and it is desired that the mask patterns do not have Hotspots.
Conventionally, when the Hotspot is found, the design layout is corrected, and the corrected design layout (entire range of the chip) is divided to generate two new mask patterns. The DRC and the LCC are again performed on the two new mask patterns. Even in such case, a new Hotspot is sometimes found at a position different from where the Hotspot was first found. In this case, the processes from the correction of the design layout to the LCC are repeated. Another new Hotspot is sometimes still found. In this case, the design layout may not be corrected, and the design period may possibly be extended. Thus, the design layout used for the double patterning is desirably corrected in a short time.